Animation on the iPhone

Question

I am coming from a long spell as a Flash developer, and find simple code-based animation on the iPhone much more difficult than in Flash using actionscript. There are several excellent free class packages called "animation kits" available for actionScript that abstract the core animation code into simple one line method calls that allow you to tween almost any property of a single or multiple objects over time. For example the code below tweens the x, y, and alpha properties of a sprite (image1) over .5 seconds, and calls a method when the tween is complete:

TweenMax.to(image1, .5, {x:100, y:100, alpha:1, ease:QuadEaseOut, onComplete:doSomething});

Are there any class packages for iPhone that give similar animation simplification?

Thanks